B373

COMMISSION OF INQUIRY INTO THE DIAPHRAGM WALL AND PLATFORM SLAB CONSTRUCTION WORKS AT THE HUNG HOM STATION EXTENSION

UNDER THE SHATIN TO CENTRAL LINK PROJECT

WITNESS STATEMENT OF KWAN PAK HEI LOUIS

FOR

MTR CORPORATION LIMITED

I, KW AN PAK HEI LOUIS, of MTR Corporation Limited, MTR Headquarters Building,

Telford Plaza, 33 Wai Yip Street, Kowloon Bay, Hong Kong, WILL SAY AS FOLLOWS:

1. I am a Construction Engineer II - Civil of the Shatin to Central Link Project (’,SCL

Project”) of MTR Corporation Limited ("MTRCL ’,). I am duly authorised by MTRCL

to make this statement on its behalf.

2. I joined MTRCL in 2014 as a Construction Engineer (’,ConE ’,) III - Civil. During my

tenure with h在TRCL, I was involved in the SCL Project as a ConE III Civil from April

2014 to December 2014, and (after I became a Chartered Engineer) as a ConE II - Civil

from December 2014 up to this date.

3. I have had personal involvement in the SCL Project from 1 April 2014 up to the date of

this witness statement. My prim缸y role for the SCL Project as ConE II - Civil is to

inspect the site works and progress. I went on site four days per week (with each visit

ranging from 30 minutes to 3 hours depending on the nature and scope of each visit) to

conduct routine site surveillance' in respect of the works generally, and I was responsible

for ca訂ying out hold point inspections of the rebar fixing works in Areas Band C (except

for bays C3 月2 and C3-3) in respect of the construction of the East West Line (’,EWL")

slab.

I S巴e PIMS/PN/11-4/ A5,’Monitoring of Site Works', paragraph 5.7.1 :’'Site surveillance is to be carried out by site inspector，αte teams to monitor day-to-d，αy site works of the Contractor. The intention is to hα：ve site issues identified early for prompt remedial action by the Contract肘， in additional [sic} to and prior to the formal inspection of the Works [ . .}'.

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4. I have obtained a Master of Engineering in Civil & Environmental Engineering 企om

Imperial College London. I am a Chartered Engineer and a member of the Institution of

Civil Engineers in the United Kingdom.

5. I am providing this witness statement in response to various matters raised in a letter

dated 27 July 2018 仕om Messrs Lo & Lo (’,Letter ’,), who I understand are the solicitors

acting for the Commission of Inquiry into the Diaphragm Wall and Platform Slab

Construction Works at the Hung Hom Station Extension under the Shatin to Central Link

Project (”Commission of Inquiry ’,). In this statement, I shall address the matters listed

as items 4, 5, 7, 8(a), 8(d), 8(i), 1 l(d), 1 l(p), 12(a）『（b), 1月d）』（e) and 13(c) of the Letter.

6. While I am aware of the matters raised in items 4, 5, 7, 8(a), 8(d), 8(i), 1 l(d), 1 l(p),

12(a)-(b), 12(d)-(e) and 13(c) of the Letter based on my first-hand observations and

personal involvement in the SCL Pr吋ect from April 2014 to March 2018, and I confirm

that the contents of this statement are true to the best of my knowledge and belief; there

are occasions when I can only speak to matters by reference to MTRCL's documents due

to the lapse of time, in which case I believe the contents of those documents are true and

correct.

Item 4: Please provide as an exhibit to the witness statement a list of the mana2:ers侖

supervisors and inspectors (with names and contact details) emploved or en2:a2:ed bv Your Companv who were involved in the steel fixin2: works and the construction of the steel structures within the diaphra2:m walls and platform slabs. Identify the type of work and duties undertaken bv such mana2:ers司 supervisors and inspectors.

7. I understand that paragraphs 7 to 13 the witness statement of Mr. James Ho (the draft of

which I have reviewed) explain the role of the ConE team as a whole on the SCL Project,

which is consistent with my understanding. I will therefore confine myself to explaining

in further detail my role as a ConE II reporting directly to Mr. James Ho (Senior

Construction Engineer (“SConE’,)) and Mr. Derek Ma (ConE I).

(i) Resvonsibilities under the Site Suvervision Plα:ns

8. Based on the acceptance letters issued by the Buildings Department (“BD’,) for Contract

1112 on the SCL Project, MTRCL had to submit a 'Site supervision plan as d可zned in

section 2(1) of the Buildings Ordinance for the proposed works' (“SSPs") to the

satisfaction of the BD prior to the commencement of the works.

60823433.8 2

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9. As a result, various SSPs have been prepared for different parts of the works, and the task

of preparing these SSPs was delegated to me:

9.1. Each SSP identifies the relevant individuals assigned as technically competent

persons (“TCP’,) of different grades under the Competent Person (“CP’,) stream,

the Registered Geotechnical Engineer (“RGE’,) stream, and the Registered

Contractor (“RC’,) stream respectively. Grades Tl to T5 refer to the seniority of the

TCPs in ascending order, and are associated with respective duties and

responsibilities under the BD' s Code of Practice on Site Supen也ion 2009 (’,CoP”)

and Technical Memorandum for Supervision Plans 2009 (“TM”), although TCPs of

higher grades may take up the responsibilities of those of lower grades and the

duties of TCPs may be combined. These five grades are largely based on the

qualifications and relevant working experience of the relevant TCP as set out in

Table 2 in Pati III of the TM.

9.2. I was responsible for compiling the CP stream. MTRCL is responsible under the CP

stream for T3 to T5 site super叮vision - there are no Tl TCPs from MTRCL. For the

excavation and lateral support (“ELS ’,) works on the EWL track level, MTRCL ’ S

T4/T5 TCP alternatives were the Construction Manager (i.e. Mr. Kit Chan until he

left the SCL Project) and the SConE (i.e. Mr. James Ho). In particular, Mr. Chan

acted as the CP Representative on site. MTR CL' s T3 TCPs were myself and Mr.

Derek Ma - we acted as T3 alternatives, in case one of us went on leave or was

otherwise unavailable. Under the CP stream, records of each site inspection carried

out by a TCP have been signed and maintained contemporaneously, and are kept on

site to this date for inspection by the BD.

10. By and large, I was responsible for preparing the CP stream section in the SSPs submitted

to the BD, and I did so based on the CoP and the TM issued by the BD.

11. In particular, I calculated the supervision requirements (i.e. the minimum frequency of

site inspection) of the TCPs assigned using Form C appended to the CoP, and with

specific reference to (amongst other things):

11.1. Paragraph 6.1 of the TM, which provides that the 'minimum requirements on the

grαdes ofTCPs αnd frequency level of inspection αppropriαte to various types of

building works or street works αre set out in Tαble 1 in this Technical

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Memorαndum. The number of TCPs αnd their frequency level of inspections should

be increased with the complexi句 of the works. ﹝．．．﹞ Detαils of the method of

αssessment of complexity αnd the eχtent thαt the number of TCPs αnd their

frequency level of inspections should be increαsed α:re set out in the Code of

Prαctice ’．

11.2. Paragraph 8 .1 of the CoP, which provides ( consistent with p缸agraph 6.1 of the

τ＇M）也就吐白‘grαdes of TCP αnd their minimum frequency level of site inspections

required for eαch functional streαm for various 句pes of building works or street

works αre set out in Tα，bfe 1 of the Technical Memorandum'.

11.3. Paragraphs 8.4 to 8.8 of the CoP, which provide th叫 the 'effect of the scαle of the

works should be considered in determination of supervision requirements' by

reference to a scale factor for each type of work, i.e. 'the ratio of the estimated

value of the measurable item of the works to the bαsic value ' as assessed according

to Table 8.1 in the CoP.

11.4. Paragraphs 8.9 to 8.11 and Tables 8.2 to 8.3 of the CoP, which divide the minimum

frequency levels of inspection into Levels 1 to 5 (based on man-days per month),

and then describe increases to the level of supervision input where a scale factor

exceeds one by multiplying the scale factor to the minimum frequency level of

inspection required for the respective type of works.

11.5. Paragraphs 8.12 to 8.17 and Tables 8.4 to 8.11 of the CoP, which explain how one

should calculate the combination ofTCPs for one or more types of building works.

11.6. Paragraph 6.2 and Table 2 of the TM and paragraphs 8.18 to 8.21 of the CoP, which

set out the minimum qualifications and experience required for each grade of TCP.

12. For my part’的 far as the construction of the EWL slab was concerned, I was assigned as

a TCP of grade T3 under the CP stream - see e.g. the SSP for 'ELS Works αnd

Substructure (Grid 22/40 and KIN) αt EWLTrαck Level for Hung Hom Stαtio況， submitted

by MTRCL on 18 June 2015 and accepted by the BD on 6 August 2015.

13. In respect of the EWL slab works specifically, Mr. Derek Ma and I were assigned as T3

alternatives under the SSP, such that we collectively discharged the duties of a grade T3

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TCP for the EWL slab works under the CP stream. Looking at the TM, our duties as

grade T3 TCP were as follows:

13.1. Paragraph 5.8 of the TM states that TCPs of grades Tl to T3 are responsible for

carrying out 'routine s可ety supervision ’, which includes 'monitoring that the site

operαtions αnd working methods meet s可ety S的ndards set out in the Buildings

Ordinance αnd respective code of practice', 'checking that general and minor

safety aspects of the building works p 缸e properly carried out, and 'checking that

work cαrried out on site complies with the approved， αccepted or submitted method

statements αndprecαutionαη1 and protective meαsures p.

13 .2. Typical 'routine items' for TCPs of grade T3 under the CP stream ( equivalent to the

'AP' stream referred to in the CoP) are set out in Table 5.1 of the CoP. Those items

include establishing systems for coordinating, compiling and filing of reports,

forwarding reports to the CP in case of non-conformances, checking the safety of

hoardings, covered walkways, scaffolding, catch fans, and checking that monitoring

check points are installed and readings are taken in time.

和） Generαi resoonsibilijies αsα ConEII

14. In co叮unction with my responsibilities under the SSPs, my role as a ConE II includes

(amongst other things) the following tasks in practice:

14.1. Considering safety as the primary objective at all times.

14.2. Supporting the contractor as much as possible to enable the works to be

successfully implemented;

14.3. Conducting regular site surveillance to uphold the site safety standards, checking

the quality of works, identifying any unsafe act on site and monitoring the work’s

progress;

14.4. Understanding and perfo口ning the duties as detailed in the Project Health and

Safety Manual;

14.5. Assisting the ConE I in reviewing the contractor’s submissions and drafting

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Engineer’s Instructions, responding to Requests for Information (“RFI"), preparing

Non-Conformance Reports (“NCR” requested;

14.6. Assisting the ConE I in liaising with Government departmen的， utilities companies,

and interfacing with designated contractors, in order to ensure the smooth delivery

of the SCL Project; and

14.7. Attending regular meetings (and other meetings when required), and preparing

weekly progress reports to the SConE. These meetings and reports do not deal with

quality matters, but generally concern issues such as site safety and progress of the

works.

15. I should add that I generally conduct routine site surveillance on my own. The site

supervisors from Leighton Contractors (Asia) Ltd (“LCAL’,) would only accompany me

if:

15.1. LCAL had requested a hold-point inspection for permission to progress to the next

stage of the works, typically by submitting a Request for Inspection/ Survey Check

("RISC吋 form﹔ or

15.2. I had identified minor defects or non-conformances during my routine site

inspections, in which case I would request LCAL to ask its sub-contractors to

rectify the issue. To be clear, and in line with general industry practice, I would not

deal with LCAL’s sub-contractors directly, and all my requests would be made to

LCAL who would then deal with their sub-contractors as appropriate.

Item 5: Describe and explain the steps. procedures and timeline in the construction and completion of the steel fixin2: works in the diaphra2:m walls and platform slabs. With reference to the said steps句 procedures and timeline. please describe and explain the respective roles and involvement of the Government有 Your Companv『 Lei2:hton司 Fan2:Sheun2:句 Intrafor and China Technology and elaborate on the interaction and relationship between Your Company and these parties on site and on a dav-to-dav working basis.

16. I refer to paragraphs 14 and 15 of the witness statement of Mr. James Ho for an overview

of the relevant method statements for the construction of the EWL and NSL slabs, which

is consistent with my understanding, and I will not repeat those details here.

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17. For the purposes of the rebar fixing works in the EWL slab, in addition to the method

statement, the drawings were also an important source of information for both LCAL and

MTRCL's ConEs. All the relevant drawings were prepared by Atkins (China) Ltd

(“Atkins”) (Team A），孔1TRCL’s Detailed Design Consultant, and these consisted of two

different sets of drawings:

17 .1. Approved drawin郎， which were submitted to and approved by the BD and

reflected the approved design intent of the works. The detailed process is addressed

in the witness statement of Mr. Andy Leung, who is the Design Manager for

Contract 1112 on the SCL Project; and

17.2. Working drawin郎， which were issued by MTRCL to LCAL for construction, and

importantly, these drawings were also issued to MTRCL’s ConE team when

caITying out RISC inspections for the rebar fixing works.

18. In essence, the EWL slab in Areas B and C is three metres thick, whereas the EWL slab

in Areas A and the Hong Kong Coliseum (“HKC’,) is one metre thick. The three-metre

slab in Areas B and C consists of layers of rebars at the top and the bottom of the slab

which are then encased in concrete, and the rebars were fixed from the bottom-most layer

upwards. The spacing and number of layers of rebars in each area bay were shown on the

working drawings issued for construction, and there were separate working drawings for

the top and bottom layers respectively.

19. The construction of the EWL slab typically consisted of the following splicing

assemblies:

19.1. The splicing of the starter bars to the cast-in couplers (both top and bottom layers)

in the excavation side of the diaphragm wall panels using Type A 2 connections,

except for the panels in the east diaphragm wall which were subject to the change

in construction detail which I will discuss below in paragraphs 40 to 43. These cast­

in couplers fonn part of the rebar cages in the diaphragm walls, and after the

concrete casting of the diaphragm walls, the cast目in couplers had to be exposed

2 I refer to the explanation of Type A and Type B connections at paragraphs 28.1 to 28.2 of the witness statement of Mr. Kobe Wong, which I have had the opportunity to review and understand to be accurate.

60823433.8 7

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(typically using a hydro-demolition machine) as part of the preparation of the shear

key.

19 .2. The splicing of starter bars to couplers (both top and bottom layers) at the

horizontal construction joints between each bay of the EWL slab, again using Type

A connections.

20. In respect of each bay of the EWL slab in Area C, the key hold司points as set out in the

Inspection and Test Plan (“ITP’,) contained in Appendix E to the Method Statement of

EWL Slab in Area C Construction submitted by LCAL on 19 June 20153 were as follows:

20.1. Inspection, sampling and testing of materials delivered to the site, including rebars

and couplers.

20.2. Inspection of cementitious corrosion inhibitor on shear key.

20.3. Survey check of soffit level, wall alignment and verticality.

20.4. Inspection of the rebar fixing works (bottom and top layers).

20.5. Pre” pour check (including cleanliness, E&M cast-in items, embedmer哎， starter bars,

construction joi肘， formwork).

20.6. Post-pour check (after concrete pouring, curing and removal of formwork).

20.7. As-built survey check.

21. As far as I can recall, no concrete pouring works were carried out in two or more adjacent

bays of the EWL slab (except bays C3-2 and C3-3) at the same time, although it was

possible that more than one bay was being constructed concurrently at different stages of

the work sequence ( e.g. concrete was being poured in one bay while other bays were at

the rebar fixing stage).

22. The rebar fixing works and the associated RISC inspections for Areas B and C ( excluding

the 1875 box culvert in Area Cl) were carried out from July 2015 to January 2016, and I

3 This Inspection and Test Plan was applicable to the EWL slab works in Areas A, B and C generally, as the top­down construction method of the EWL slab applied in largely the same manner to those areas.

60823433.8 8

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understand that a bay-by-bay schedule of dates will be disclosed to the Commission of

Inquiry.

Item 7: Describe and explain Your Companv’s svstem and measures in place at the material time to ensure that the steel bars in the diauhra2:m walls and olatform slabs were properlv installed and connected in compliance with Reauirements. Standards and Practice and that anv irre2:ularities、 non咀compliances and defects will be reported and addressed bv the appropriate parties and/or persons. Please adduce all related manuals. records and documents on this topic.

向 Insvection of rebar 你inz works and couvler connections

23. In the paragraphs to follow, I will address the division of labour in practice (between

IOWs and ConEs) in relation to the site surveillance and inspection of the diaphragm

walls and EWL slab.

24. I was not responsible for any of the RISC inspections in respect of the diaphragm walls,

and it was the IOWs who conducted site surveillance and RISC inspections in respect of

the pre-fabrication and installation of the steel rebar cages, including the coupler

connections between those cages. My responsibility, as far as relevant to this

Commission of Inquiry, was inspecting the rebar fixing works in the EWL slab in Areas

Band C.

25. At the time of the EWL slab works, I was not aware that a document entitled 'Quality

Supervision Plan on Enhanced Site Supervision & Ind己pendent Audit checking By MTRC

& RC for Jr,叫αllation of Couplers (Type II - SE/SPLICE Stαndαrd Ductility Coupler)'

(“QSP’,) was issued by LCAL and submitted to the BD in 2013. This was because the

QSP was not discussed in the induction when I first joined MTRCL in April 2014, or in

any other training session or meeting which I have attended.

26. Nevertheless, I was aware of the requirements in the BD’s acceptance letters in relation to

quality supervision of coupler splicing assemblies. Further, I was aware of the practice in

Contract 1112 which had already been put in place by the time I joined in 2014, namely

that the IOWs were responsible for routine site surveillance in respect of splicing

assemblies using couplers in the diaphragm walls.

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27. When it came to the construction of the EWL slab upon the completion of the diaphragm

walls, the ConEs (and not the IOWs) were responsible for inspecting the rebar fixing

works and signing off the RISC forms for that hold” point.

28. At the time, I took this division of labour to mean that the ConEs would inspect the top

and bottom layers of the rebars within the EWL slab as and when they were completed,

while the IOWs would continue to conduct daily site surveillance in respect of the

construction works generally, including the splicing of starter bars to the cast-in couplers

at the wall-to自slab and slab-to-slab joints.

29. That said, it is important to note that there was collaboration and co-ordination between

the IOW and ConE teams whenever appropriate, and we worked together generally on

matters relating to site surveillance and inspections.

30. I refer to paragraphs 33 to 36 of the witness statement of Mr. Kobe Wong, which describe

in some detail the use of the four-ply RISC form and the general administrative process

relating to the submission, receipt and endorsement of RISC fonns. I agree with what Mr.

Wong has said.

31. I am aware that the RISC process (based on hold-points in the ITP) is outlined in broad

tenns in paragraphs 5.1.1 to 5.1.2 of the PIMS Practice Note on 'Monitoring of Site

Works' (PIMS/PN/11-4). However, neither the PIMS documentation nor the ITP

specifies the standards or requirements which must be taken into account when carrying

out the RISC inspections. As such, I think it would be helpful for me to expl叫n in more

detail the manner in which I carried out the RISC inspections, and I will do so in

paragraphs 55 to 60 below in response to item 12(d）。f the Letter.

(ii) Nor卜Conformance Reρarts

32. Whenever I observed any issues with the workmanship or quality of the works, I tried to

resolve the issue on the spot by liaising with LCAL’s representatives on site. A Non­

Conformance Report (“NCR’,) would only be raised if there was a non-conformance in

the final product, or if there was a recurrent non-conformance which could not be

resolved. It should not be issued for minor defects reported in routine inspections.

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33. To be clear, MTRCL’s NCRs are internal and based on the guidance in the PIMS

Procedure for ℃onstruction Manαgement'4 and the Practice Note on 'Monitoring of Site

Works ’5. This is distinct from the BD ’s Form B non-conformance and rectifications

report referred to in paragraph 5.4 of the CoP, which is aimed at notifying the BD of any

non-conformities that pose an imminent danger or cause a material concern for safety -

such non-conformities have to be reported to a TCP of grade TS and ultimately to the

CP/CP representative. I have not issued any Form B report in respect of the EWL slab

works.

34. If an issue was escalated to the SConE, Mr. James Ho, and he decided to issue a NCR, he

often delegated the drafting of the NCR and the preparation of the attachments to the

ConEs, and once reviewed and approved by Mr. Ho, the Construction Manager would

issue the NCR to LCAL, and remedial proposals/responses were typically submitted

through the ePMS.

35. Where there were serious non-conformances in the works, the construction management

team identified those non-confonnances and issued NCRs to LCAL pursuant to the PIMS

guidelines, and the ConE team followed up on these NCRs to ensure that the issues were

properly closed out. From a frontline perspective, there is a proper system in place to

identify non-confonnances, escalate matters when necessary, and to ensure the

rectification of the non-conformances. As far as I am aware, MTR CL has not issued any

NCRs relating to the cutting or shortening of rebars which forms the subject-matter of

this Commission of Inquiry.

Item 8: （的 Explain and confirm whether Your Comoanv has anv knowledee of the Defective

Steel Works (whether undertaken by Leiehton and/or its sub-contractors) and if so. identify and describe the relevant events and occasions.

( d) If the events and occasions were reported to vou bv vour manaeers司 supervisors.inspectors and/or other persons. identify the person(s) who made the reports to you.

(i) Provide Your Company’s confirmation that‘ other than the events and occasions cited in Your Company’s reply to this paraeraph‘ Your Company is not aware of any other Defective Steel Works in the diaphraem walls and platform slabs.

36. I learned about the cutting of threaded ends of rebars for the first time from the email

dated 15 December 2015 企om Mr. Kobe Wong (SIOW 11) to LCAL, as I was copied in to

4 PIMS/P/11, paragraphs 10.3.1 to 10.3.5. 5 PIMS/PN/11-4, paragraphs 5. l.2(g), 5.3.4, and Exhibit 7.9.

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that email. In that email, Mr. Wong reported 曲的 ＇our AIOW and under [his] routine

inspection to threaded bars, at 3m thickness EWL slab at Area C3bay C3-2 I C3-3, was

戶und 5 number of threaded steel bars heads ’, and that the 已remedial works was

conducted immediαte﹛y and witnessed by our AIOW at night time'.

37. I do not have any first-hand knowledge of or involvement in the incident, as the incident

had already been resolved by the time of Mr. Wong’s email, and I was not responsible for

inspecting the rebar fixing works in bays C3 ” 2 to C3-3. In any event, I understand that the

incident is explained in full in paragraphs 77 of 84 of the witness statement of Mr. Kobe

Wong. Other than the incident referred to in Mr. Wong’s email (which I was copied into),

I am not aware of any other incidents in which the threaded ends of rebars have been cut.

38. I do know as a fact that Mr. Jason Poon of China Technology attended some of our

Weekly Works Meetings - these were typically attended by MTRCL's ConEs, LCAL’s

represent前ives and subcontractors' representatives. Mr. Kit Chan (Construction Manager)

chaired those meeting until he left the SCL Project, when Mr. James Ho (SConE) took

over Mr. Chan's role. Based on the meeting minutes which I have managed to review in

the limited time available to date, Mr. Poon attended a weekly works meeting for the first

time on 3 March 20呵， and continued to attend those meetings until at least the end of

November 2016, but as far as I can recall (and the minutes of those works meetings

confirm) Mr. Poon did not mention any issues regarding the rebar fixing works or coupler

connections in any of those meetings.

Item ll(d): Confirm whether Your Companv has anv additional information and materials to supplement the MTRCL Report and if so‘。lease adduce such additional information and materials bv wav of a supplemental report.

39. During my routine site surveillance activities, I have personally observed the top of the

east diaphragm wall panels being hacked off, followed by the replacement of the coupler

connections therein with through-bars. Based on the site photos of the east diaphragm

wall which I have managed to review to this date within the limited time available, this

change has been implemented in the majority of panels in the east diaphragm wall, except

for a limited number of panel where the top of the panel was not trimmed and the coupler

connections were retained:

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39.1. Underpinning in Area B: panels EH 44 (3 layers of coupler connections) and EH 45,

物，鉤， 51 and 57 (3 to 4 layers of coupler connections).

39.2. Capping beam in Area B: panel EH 40 (coupler connections on excavation side

only).

39.3. Area Cl-1, consisting of two panels in the initial bay of the EWL slab works

constructed according to coupler connection details: panels EH 73 and 75.

39.4. Areas Cl-1 and Cl-2, constructed according to the LCAL’s remedial proposal

(sketch SK-0034-001) for Technical Query 34, on which Atkins Team B had no

adverse comment: panels EH 69, EM 70, EH 71, EM 72 and EH 74 (through-bars

in row Tl from the EWL slab up to the soil side of the diaphragm wall; all coupler

connections were kept in the other layers).

40. I was aware of the agreement within the construction management team that the change

in construction detail was considered acceptable at that time. In particular, ,upon

reviewing my own records within the limited time available, I recall that I was forwarded

at least three relevant emails by Mr. James Ho (SConE) in July 2015:

40.1. An email dated 8 July 2015 (timed at 20:51) to MTRCL’s Mr. Kenneth Tan

(Design Management Engineer I) from LCAL’s Mr. Johnson Luk (Risk Manager),

who attached ( amongst other things) a 'Design Report for HUH Station Primα；y

Structure' (Deliverable No. TWD-004B3) prepared by Atkins' Team B for LCAL

(and which was ultimately submitted by MTRCL's Design Manager, Mr. Andy

Leung, to the BD on 29 July 2015). Mr Ho forwarded this email chain to myself

and Mr. Derek Ma (ConE I）。n 9 July 2015 at 08:09. I note in particular that section

6.2 of the attached design report included the following statements:

60823433.8

'The top of diαphrαgm wαll pαnel will be trimmed to the lowest level of top rebar for the EWL slαb (min 420mm below the top level of EWL slαb).

The top rebar of EWL slab αt the diαphrαgm wαll pαnel will then fl，χ to the top rebαr ofOTE [ i.e. Over TrαckExhα：ust] slαb to αchieve full tension iαps.

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The EWL slab and OTE slab will be cαsted concurrently with temporary openings around the existing columns and pile caps. ’

40.2. An email dated 24 July 泊的（timed at 16:20) to LCAL from Mr. Wan Cheung Lee

of Atkins' Team B, who 'reminded that in order to comply with the design

αssumption, the OTE wall must be concrete/pour together at the same time

(monolithically) with the 3m EWL slαb '. Mr Ho forwarded this email chain to

myself and Mr. Derek Ma (ConE I) on 25 July 2015 at 09:43.

40.3. An email dated 25 July 2015 (timed at 14:05) from Mr. Rob McCrae of Atkins’ Team A to MTRCL's Mr. Brandon Reilly, which stated that the OTE slab could

only be cast after the EWL slab if that w的 done before future activities would

如rther load the structure. Mr Ho forwarded this email chain to myself, Mr. Derek

Ma (ConE I), Mr. Wing Chen (ConE I), Mr. Kingsley Lam (ConE II), Mr. C.K.

Cheung (ConE II), and Mr. Dick Kung (SIOW）。n 27 July 2015 at 08 :46.

41. Atkins was included in the email chains referred to above, as were MTRCL's senior

supervisors/managers e.g. Mr. Brendan Reilly (Project Manager), Mr. Jason Wong

(General Manager/Competent Person for Contract 1112), Mr. Andy Leung (Design

Manager) and Mr. James Ho (SConE). As I was only a ConE II and not responsible for

any design matters, I implemented what Atkins proposed and what the more senior

members of the construction management team had discussed and agreed.

42. In any event, from an engineering point of view, it made perfect sense to me that if the

'design αssumption' was for the EWL and OTE slabs to be cast monolithically - and at

the same time, through-bars should be used instead of several bars connected by couplers

- this would reduce the number of splicing assemblies and thus the risk of non­

conformances in the construction process.

43. For my pa哎， I carried out the RISC inspections by checking the rebar fixing works

against the working drawings for the EWL slab issued to LCAL for construction in

August and September 2015 respectively (as detailed in paragraph 53 below), and that

exercise was not affected by the change in construction detail because:

60823433.8 14

B387

43 .1. The working drawings issued by Atkins' Team A for the construction of the EWL

slab only showed the rebars within the slab, which were not subject to any changes.

The connection details had to be ascertained from a separate coupler schedule,

which indicated two layers (Tl and T3) of top rebars connecting the EWL slab to

the top of panels EH 40 to EH 115 in the east diaphragm wall: see working drawing

no. 1112/W/HUH/ATK/C12/607 Rev A.

43.2. Accordingly, for the panels in which coupler connections were replaced with

through-bars, I inspected the connection details based on the working drawings

issued for construction, and I checked the through-bars extending 仕om the EWL

slab across the east diaphragm wall based on the same spacing and Tl/T3 layers as

specified in the original coupler schedule. I will illustrate this in more detail by

reference to a few concrete examples in paragraph 56 below.

43.3. Since July 2018, MTRCL’s construction management team has been checking the

drawings against the site records to double check the 臼11 extent of the change in

construction detail. I have assisted in collating and compiling the relevant site

photos (from MTRCL’s project server) showing the top-layer slab-to『wall

connection details in Areas B to C. Examples of these photos are shown in

paragraphs 56.1 to 56.3 below.

44. By the time the MTRCL Report of 15 June 2018 was being prepared, the construction

management team had to provide an estimate of the total number of couplers, while we

were all collating a large amount of information and documents at the same time. The

estimate was provided based on the BA-14 刮目built drawings for the diaphragm walls

within a very tight timeframe, such th叫 we were not aware of the discrepancies in those

as『built drawings at the time. I refer to the witness statements of Mr James Ho

(paragraphs 72 to 78) and Mr Derek Ma (paragraphs 42 to 43), which also expl位n the

circumstances at the time.

Item ll(p): Explain whether it is common in the construction of diaphra2m walls and platform slabs for steel bars to be shortened and cut and confirm whether such shortenin2 and cuttin2 of steel bars within the diaphra2m walls and platform slabs is acceptable and in compliance with Recrnirements. Standards and Practice.

45. To the best of my knowledge, other than the cutting of the 12-met閃閃b訂s （的 delivered)

to the correct length for the rebar fixing works using a bar bending machine, there should

60823433.8 15

B388

be no need to cut the rebars or the threaded ends in the work areas, whether with wire

cutters or otherwise.

Item 12: （的 Describe at which sta2:e the steel fixin2: works would be inspected bv Your Company

and Leil!hton. (b) State how freauentlv Your Company and Leil!hton would carrv out the inspections. (d) Describe and explain how the inspections would be carried out. whether they were

visual inspections onlv or eauipment was used or both. (e) Confirm whether reports or records were kept followin2: the inspections and if so.

please produce such reports and records.

車） Stα史eαnd f示eauencv αt which rebar fixin史 works were insve!;_tg

46. As a TCP of grade T3, the frequency of my routine site surveillance activities is 4 times

(i.e. 4 days) a week under the SSPs submitted by MTRCL to the BD. However, the

frequency of the RISC inspections (i.e. at the hold-points for the rebar fixing works in

each bay) depended on the progress and date of completion of the rebar fixing works in

each bay.

47. I was initially responsible for inspecting the rebar fixing works in Areas B to Cl of the

EWL slab, but I also ended up inspecting Areas C2 and C3 to step in for Mr. Kingsley

Lam’的 he was busy with the preparation of the BA-14 as-built submissions for the

diaphragm walls at that time. I was therefore the person signing off the RISC forms for

all the bays in Areas B and C ( except bays C3♂ and C3-3, which were inspected and

signed off by another ConE I, Mr. Jeff Cheung).

48. The RISC form in relation to each bay of the EWL slab covered the inspection of the

rebars in both the top layers and the bottom layers. However, I should stress that the

inspection of each bay was not done on a single occasion - as a matter of common sense,

if the top layers had already been completed, it would be difficult to visually inspect the

bottom layers. Therefore, I typically inspected the bottom layers of rebars once they had

been completed (and prior to the commencement of the fixing of the top layers of rebars),

and then returned for a second inspection once the fixing of the top layers of rebars had

also been completed.

60823433.8 16

B389

49. In practice, LCAL’s representative ( e.g. Mr. Edward Mok and Mr. Man Sze Ho, who

were LCAL’s graduate engineers) usually contacted me when the fixing of the bottom

layers of rebars had started in order to request an inspection of those bottom layers. There

were also occasions when I personally observed the commencement of the fixing of the

bottom layers during my regular site surveillance activities and inspected those layers

whilst on site. In any event, it was not difficult to know the location and status of the

rebars being fixed at any given point in time, as the rebar fixing works were not carried

out in many different bays at the same time, and we knew by and large the relevant bays

and layers which were going to be ready for inspection.

50. The RISC forms were meant to be submitted by LCAL to MTRCL in advance of the

intended date of the hold point inspection, but LCAL was often late with its paperwork

and submitted the RISC forms after the relevant works had already been completed

(hence many RISC forms were marked as ＇／αte submission' in the notes/comments

section), even though I verbally reminded LCAL on multiple occasions to submit RISC

forms in advance of the intended hold point inspections. In practice, an arrangement was

in place on site such that I was requested by LCAL to inspect the top and bottom layers

of rebars in each bay on separate occasions. For the bays which I have inspected, I am

confident that the top and bottom layers of rebars have both been inspected on a spot­

checking basis, in order to ensure that they had been properly fixed before I signed each

RISC fonn and gave permission for LCAL to proceed to the next stage of the works.

51. I should point out that my involvement in the RISC process was largely confined to

carrying out the hold-point inspections on site. After giving permission for the works to

proceed to the next stage and completing Part C of the RISC form, I had no involvement

in the subsequent endorsement by the SIOW of the form or the filing of the completed

form in the ePMS (which is explained in paragraphs 33 to 36 of the witness statement of

Mr Kobe Wong), the latter of which was LCAL’s responsibility as far as I recall.

(ii) WQrkin史 drα：win史s used for RISC insvections of rebar fixin史 works

52. When carrying out RISC inspections for the rebar fixing works in the EWL slab, I did so

largely by reference to the working drawings (as already mentioned in paragraph 17

60823433.8 17

B390

above), and also taking into account my own engineering experience and professional

judgment.

53. The rebar fixing works in the EWL slab began with the 1875 box culverts and bay Cl-1.

In respect of these areas, I carried out the RISC inspections for the relevant rebar fixing

works by reference to:

53.1. For the area known as the ‘1875' box culverts (Gridlines 30 to 31), the rebar fixing

works were carried out from 10 March to 27 May 2015. I refe叮ed to working

drawing no. 1112用T/HUH/ATK/C12/181 Rev. B which was issued on 25 October

2013 and was current at the time - this drawing indicated two rows of top layer

rebars (Tl and T3) from the EWL slab across the diaphragm wall, which matched

the number of rows and spacing as constructed. I should add that at this location,

the cut- level of the east diaphragm wall (panels EH 75 and EM 76) is lower tha n

at other locations to cater for the box culvert construction, such that through-bars

were adopted from the EWL slab across the diaphragm wall up to the OTE/soil side.

53.2. For bay Cl-1 (Gridline 28.5 to 30), the rebar fixing works were carried out from 13

July to 25 July 2015. Apart from panel EH 74 (which was constructed as per the

remedial proposal in response to TQ 34 with the first row in the top layer replaced

with a through-bar), the slab『to-wall connections followed the coupler connections

and number of layers in the diaphragm wall as reflected in the BA-14 as-built

submissions for the diaphragm walls.

54. After the completion of the rebar fixing works in bay Cl ” l and the 187 5 box culverts,

立1rther working drawings were provided by Atkins' Team A to MTRCL's design

management team (“DM Team"), who in turn issued the working drawings to LCAL and

the ConE team for construction. Having looked back at my own records and

correspondence within the limited time available to date, I have identified the sets of

working drawings issued for the construction of the EWL slab in Areas B and C, which

can be summarised as follows:

Date of email

60823433.8

Description

18

Key working drawings

Bays I Concrete covered I casting

B391

attached date 19/06/2015 Atkins' Team A uploaded C12/607 Rev. B B to C

working drawing C12/607 Rev. B dated 15 June 2015 (Coupler Schedule for Areas B to C) onto ePMS.

11/08/2015 Mr Edward Tse (Atkins Cl2/180 Rev. Dl Cl-2 22/08/2015 at 16:36 Team A) sent Mr. Kevin Yip C12/181 Rev. Cl Cl-3 。7/09/2015

(DM Team) the ‘updαted C12/182 Rev. C2 C2-5 14/09/2015 working drawings with DIL C12/605 Rev. Bl for Areα Cl αnd C2 for your Cl2/606 Rev. Cl αdvαnee informαtion '. These C12/017 Rev. A2 were 'adναnee check prints', Cl2/018 Rev. Al and were issued to LCAL in order to avoid holding up the construction works on site.

11/08/2015 Mr. Andy Leung (DM Team) at 19:28 sent 恥1r. Justin Taylor and

LCAL's Mr. Philip Daynes an ‘αdvαnee set of updated EWLslαb Working Drαiwings of Areα Cl &C2 for your construction ’. Mr. James Ho (SConE) and Mr. Kit Chan ( Construction Manager), amongst others, were copied into this email.

12/08/2015 Mr. James Ho (SConE) at 08:17 forwarded the working

drawings to ( amongst others) myself and Mr. Derek Ma.

22/09/2015 Mr. Kenneth Tan (DM C12/179 Rev. D Cl-4 29/09/2015 at 13:47 Team) sent to LCAL ’ s Mr. C12/180 Rev. D C2個6 。7/10/2015

Justin Taylor 'the latest EWL C12/181 Rev. C C2-3 08/10/2015 slαb in ./Qrmal revision for C12/182 Rev. C C3-5 24/10/2015 your αdvαnce informαtion C12/183 Rev. C C2-4 29/10/2015 αnd site construction'. Mr. C12/184 Rev. B C3 ” 6 。7/11/2015

James Ho (SCon日 and Mr. C12/605 Rev. B C3-l 10/11/2015 Kit Chan ( Construction C12/606 Rev. C C2-1 23/11/2015 Manager), amongst others, C12/017 Rev. A B『2 25/11/2015 were copied into this email. C12/018 Rev. A C3-4 30/11/2015

60823433.8 19

B392

22/09/2015 扎，fr. Kenneth Tan (DM B-3 09/12/2015

at 13:49 Team) issued the 'EWL slab B-1 15/12/201 5

layout α:nd rebαr detαii for Cl-5 23/12/2015

construction ' to MTRCL’s C3-2 28/12/2015 Mr. CK Cheung, copying in C3-3 28/12/2015

myself, Mr. Derek 1\鈕， and B-4 12/01/2016 Mr. Wing Chen. B-5 12/01/2016

(iii) Mα:nner of carrvin史 out RISC insvections of rebar fixin史 works

55. The RISC inspections for the rebar fixing works were conducted visually on the basis of

the working drawings. I would typically check the spacing of the rebars with a tape

measure, the number of rows/layers of rebars, the lap length of the lapped rebars, and the

diameter of the rebars used.

56. In order to illustrate how I checked the rebar fixing works against the working drawings

during RISC inspections, I set out three random examples below. For convenience, all

three examples relate to the slab-to-wall rebar connection details on the east diaphragm

wall, in order to demonstrate how I was able to inspect the rebar connections based on the

working drawings after the change in construction detail discussed above:

56.1. Example 1 - Panel EH 42 (Area Bl, Gridline 16):

60823433.8

56.1.1. Working drawing no . 1112/W/HUH/ATK/C12/179 Rev. D dated 21

September 2015 (Image 1) referred to the coupler schedule in working

drawing no. 1112/W/HUH/ATK/C12/607 Rev. B dated 16 June 2015

(Image 2) (both of which were current at the time), which indicated two

rows (Tl and T3) of T40 top layer rebars connecting the top of the east

diaphragm wall to the EWL slab, with a spacing of 150 mm centre-to­

centre.

Image 1: drawing no. 179 Rev. D- annotation referring to drawing no. 607 Rev. B

20

B393

,a[, e 扎 ι

l ( AI b 內－＜ o ﹜

Image 2: drawing no. 607 Rev. D - top rows (Tl and T3) at the top of EWL slab

56.1.2. I have checked that the number of rows/layers, spacing and diameter of the

rebar connections observed on site were consistent with the working

drawings, and this is confinned by the relevant site photo (Image 3),

which show two as-built rows of top layer through-bars connecting the

EWL slab and the east diaphragm wall. 6 The relevant drawings are

Image 3: site photo showing through-bars in the top layer of panel EH 42

56.2. E xample 2 - Panel EH 47 (Area B2, Gridline 18):

56.2.1. Working drawing no . 1112/W/HUH/ATK/C12/179 Rev. D dated 21

September 2015 (Image 4) referred to the coupler schedule in working

drawing no. 1112/W/HUH/ATK/C12/607 Rev. B dated 16 June 2015

(Image 5) (both of which were current at the time), which indicated two

rows (Tl and T3) of top layer rebars connecting the top of the east

diaphragm wall to the EWL slab, with a spacing of 150 mm centre-to­

centre.

6 Thus supers巴ding the details in BA-14 as-built diaphragm wall drawing no. 1112/Z/HUH/LCA/C12/820 Rev. A (Developed Front Elevation of Permanent D-Wall Panel EH42 - Section A) and 1112/Z/HUH/LCA/C12/607 Rev. A (Coup！巴r Schedule for Area B), which showed four top layers of slab-to司wall coupler connections.

60823433.8 21

B394

Image 4: drawing no. 179 Rev. D - annotation referring to drawing no. 607 Rev. B

Image 5: drawing no. 607 Rev. D - top rows (Tl and T3) at the top of EWL slab

56.2.2. I have again checked that the number of rows/layers, spacing and diameter

of the rebar connections observed on site were consistent with the working

drawings, and this is confirmed by the relevant site photo (Image 6),

which show two as-built rows of top layer through-bars connecting the

EWL slab and the east diaphragm wall. 7 The relevant drawings are

contained in Appendix 2 hereto.

Image 6: site photo showing through-bars in the top layer of panel EH 47

7 Thus superseding the details in the BA-14 as-built diaphragm wall drawings no. 1112/Z/HUH/LCA/C12/679 Rev. A (Developed Front Elevation of Permanent D-Wall Panel EH49 - Section A) and ll 12/Z/HUH/LCA/C12/607 Rev. A (Coupler Schedule for Area B), which showed three top layers of slab-to-wall coupler connections.

60823433.8 22

B395

56.3. Example 3 - Panel EM 96 (Area C2-6/C3-1, Gridline 40):

56.4. Working drawing no. 1112/W/HUH/ATK/C12/182 Rev. C dated 21

September 2015 (Image 7) clearly indicated two rows (Tl and T3）。fT40

top layer rebars connecting the top of the east diaphragm wall to the EWL

slab, with a spacing of 150 mm centre-to-centre. The coupler schedule in

working drawing no. 1112/W/HUH/ATK/C12/607 Rev. B dated 16 June

2015 (Image 8) indicated the same detail.

Image 7: drawing no. 182 Rev. C - annotation referring to top rows (Tl and T3)

Image 8: drawing no. 607 Rev. D - top rows (Tl and T3) at the top of EWL slab

56.5. Yet again, I have checked that the number of rows/layers, spacing and

diameter of the rebar connections observed on site were consistent with the

working drawings, and this is confinned by the relevant site photo (Image

9), which show two as-built rows of top layer through-bars connecting the

EWL slab and the east diaphragm wall . 8 The relevant drawings are

contained in Appendix 3 hereto.

8 Thus superseding the details in BA-14 as-built diaphragm wall drawings no. 1112/Z/HUI-I/LCA/C12/611 Rev. B (Developed Front Elevation of Permanent D-Wall Panel Type 1 - Section A) and 1112/Z/HUH/LCA/C12/834 Rev. C (Coupler Schedule for Area C), which were applicable to panel EH 91 and showed three top layers of slab-to­wall coupler connections.

60823433.8 23

B396

Image 9: site photo showing through-bars in the top layer of panel EM 96

57. There were also areas where the rebar connection details were subject to revisions by

Atkins (Team A) as a result of RFis from LCAL to MTRCL. For example, in panels EH

85 to EH 89 in Area C2-4, the top of the diaphragm wall was trimmed off and converted

into a three-metre capping beam on those panels, based on the drawings attached to the

response of Atkins to LCAL's RFI 001250 dated 16 October 2015 (see Appendix 4).

Through-bars were used given that the cast-in couplers had been hacked off.

58. Although my understanding at the time of the EWL slab works was that the IOWs were

responsible for conducting site surveillance in respect of the coupler splicing assemblies,

I nonetheless observed the conditions of the coupler connections generally when

inspecting the top and bottom layers of the rebars.

59. As part of my inspections, there were occasions when I spot-checked the splicing

assemblies by asking LCAL’s representatives ( e.g. Mr. Edward Mok) to instruct the

workers on site to unscrew ce1iain starter bars from the couplers and expose the threaded

end of those rebars, and then screw the bars back into the couplers. To be clear, and in

line with general industry practice, I never bypassed LCAL to deal with the

subcontractor's workers directly.

60. Based on the inspections described above which I conducted on a spot-checking basis, I

signed off on the RISC forms for rebar fixing works in Areas B and C ( except bays C3-2

60823433.8 24

B397

and C3-3），的 I was satisfied with the safety and integrity of the rebar structures from an

engineering perspective and the compliance of the rebar fixing works with the working

drawings issued in August/September 2015 (as outlined in paragraph 53 above).

61. I can confirm that the rebar fixing works under my watch were always inspected on site

before LCAL was permitted to progress beyond the hold-point to the next stage of the

works. Indeed, by the time of the pre-pour check, if there were any doubts as to the

existence/endorsement of a RISC form for the rebar fixing works in any given bays, the

IOWs would ask us to check if we had inspected the rebar fixing works before

conducting the pre-pour check and granting permission to proceed. I do not recall this

happening in relation to the areas/bays which I have inspected.

(iv) List of RISC forms for rebar fiχin史 works in Areαs BαndC

62. I understand that the RISC forms which I have signed off will be disclosed to the

Commission of Inquiry together with all other relevant materials. These RISC forms can

be chronologically summarised as follows:

Area/Bay RISC Form No. Date of Receipt of RISC Form by MTRCL

Cl-1 8092 27/07/2015 (late submission) Cl-2 8258 13/08／泊的 (late submission) Cl刁 8424 。7/09/2015 (late submission) C2-5 8425 07/09/2015 Cl-4 8563 29/09/2015 (late submission) C2-6 8595 的/10/2015 (late submission) C2月3 8596 05/10/2015 (late submission) C3-5 8702 26/10/2015 C2自4 8728 28/10/2015

C3-6 8802 05/11/2015

C3-1 8845 10/11/2015

C2” 1 8953 19/11/2015 B-2 8985 23/11/2015

C3-4 9013 25/11/2015 (late submission) B-3 9138 05/12/2015 B-1 9217 11/12/2015 Cl-5 9243 15/12/2015 B-4 B-5

9500 。8/01/2016

60823433.8 25

B398

Item 13(c): Confirm whether workers emrn2ed bv Lei2:hton and/or its subcontractors had used hvdraulic cutters to shorten and cut the steel bars embedded or to be embedded within the diaohra2m walls and olatform slabs and if so. 。lease identifv the workers and/or entities who carried out such shortenin2 or cuttin2 work bv hvdraulic cutters‘ and the oersons and/or entities who 2:ave instructions （的 for such work to be carried out and (ii) for hvdraulic cutters to be acauired.

63. I have not seen any hydraulic cutters on site, whether during my RISC inspections or

routine site surveillance activities. I am not aware of any other work activities in Contract

1112 on the SCL Project which required a hydraulic cutter. As far as I am concerned, I

am not aware of and have never seen any cutting or shortening of rebars or threaded ends

of rebars by LCAL and/or its sub-contractors using hydraulic cutters.

64. Finally, I would like to mention the following:

64.1. The events in question and which form the subject matter of the Commission of

Inquiry took place several years ago and my recollection of every detail is not

therefore perfect.

64.2. Accordingly, in preparing this witness statement I have reminded myself of the

events in question by reference to various hard copy and electronic documents and

materials, including contemporaneous email correspondence, meeting minutes and

contractual documents and other records. I understand these materials were

retrieved by MTRCL’s Legal Department, with the assistance of the MTRCL's

external lawyers, Mayer Brown.

Dated 13th September 2018

f ~ r, l• r

KW AN Pak Hei Louis

60823433.8 26